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211.
We describe changes in the morphology of the oviductal epithelium of an oviparous skink, Lampropholis guichenoti, during the course of egg production and oviposition: to characterize the luminal epithelial changes; to provide a baseline for understanding uterine changes in viviparous species; and to establish whether the plasma membrane transformation of uterine epithelial cells is indeed a feature restricted to viviparous species. Oviducts from vitellogenic, gravid, and postgravid females were observed using scanning electron microscopy. Cellular characteristics of the oviductal epithelium previously used to determine the plasma membrane transformation were assessed morphologically. Three anatomically different areas were defined within the oviduct, but no plasma membrane transformation was observed in the oviparous skink, suggesting that this is a phenomenon particular to viviparity. 相似文献
212.
Peptides containing Arg-Gly-Asp (RGD) have been used to decrease thrombosis by competitive inhibition of the integrin glycoprotein, alphaIIb/beta3a, in platelets. However, they have a short half-life in vivo. A naked plasmid, pCMV-RGD, was transferred into the skeletal muscle of mice and RGD gene expression was observed by RT-PCR. The bleeding time between control mice and RGD-transferred mice was prolonged from the 10th day to the 80th day after gene transfer while the blood glucose and serum insulin-like proteins remained at normal levels. These results provided a convenient and effective approach to relieve patients from thrombi in a single step over a relatively long period. 相似文献
213.
Human papillomavirus (HPV) infections play a crucial role in the progress of cervical cancer. The high-risk HPV types are frequently associated with the development of malignant lesions. Some of the latest studies have demonstrated that the high-risk HPV 16 and 18 are predominantly detected in the more aggressive cancers. In the present study, we aimed to establish the proteomic profiles and characterization of the tumor related proteins by using two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS). For proteomic analysis, patients infected by HPV 16 or 18 were included in this study. We compared nuclear protein and cytoplasmic protein, separately by using the subcellular fraction. Differential protein spots between cervical cancer with high-risk HPV, HPV 16 or HPV 18, and HaCaT cell lines were characterized by 2-DE. Those proteins analyzed by peptide mass fingerprinting based on MALDI-TOF MS and database searching were the products of oncogenes or proto-oncogenes, and the others were involved in the regulation of cell cycle, for general genomic stability, telomerase activation, and cell immortalization. However, there was no difference in protein characterization for cervical cancer between HPV 16 and HPV 18 infection. Nonetheless, these data are valuable for the mass identification of differentially expressed proteins involved in human uterine cervical cancer. Moreover, the data has enormous value for establishing the human uterine cervical cancer proteome database that can be used in screening a molecular marker for the further study of human uterine cervical cancer, and also for studying any correlation among the cancers induced by HPV. 相似文献
214.
Protein engineering techniques were employed to graft the known anticoagulant Arg-Gly-Asp (RGD) motif-containing sequences onto the surface of a mutant, inactive insulin framework. To probe the effect of a disulfide bond on the resultant anticoagulant activity, a native RGD-containing sequence from disintegrin dendroaspin, CFTPRGDMPGPYC, as well as a modified sequence, SFTPRGDMPGPYS, were each examined. The peptide was placed between the C-terminal of the B chain and the N-terminal of the A chainand connected with B27 and A1 residues of the inactive insulin that lacks the characteristic intramolecular A6-11 disulfide bondwithin the A chain. The two RGD-containing insulin genes were over-expressed in E. coli, and purified and designatedas RGD-Cys-Ins and RGD-Ser-Ins, respectively. Their amino acid compositions and mass data were in good agreement with those ofexpected. The RGD-Cys-Ins showed inhibition of platelet aggregation with an IC50 of 3 M, while the latter was3.5-fold less active. The in vivo assay also indicatedthat the RGD-Cys-Ins had a higher activity in prolonging the bleeding time in mice than RGD-Ser-Ins. Both RGD-Cys-Ins and RGD-Ser-Ins retained about 25% of the proinsulin immunoactivity and had almost no insulin receptor binding activity. The results indicate the necessity for the RGD motif to be conformationally constrained for it to elicit a greater anticoagulant activity. 相似文献
215.
Identification of differentially expressed genes in human uterine leiomyomas using differential display 总被引:1,自引:0,他引:1
INTRODUCTIONUterine leiomyomas (ULs) have been consideredto be of uniceIIular origin[l1. It is one of the mostcommon benign tumors, occurring in 20% to 30% ofwomen[2], accounting for significant morbidity andusually need major surgery[3] which might causesome side effects afterwards[4]. Therefore, to de-velop certain drug treatments instead has been thehope of these patients for a long time. Using alter-native approaches fOr studying patients sufferingfrom leiomyoma in various ethnic gr… 相似文献
216.
Catherine A. VandeVoort Theodore L. Tollner Alice F. Tarantal James W. Overstreet 《Molecular reproduction and development》1989,24(3):327-331
Previous studies from this center have indicated that the cynomolgus macaque (Macaca fascicularis) may serve as a model for human sperm interaction with the cervix and uterus. In some macaque species, transcervical aspiration of the uterine contents carries a significant risk of disturbing the cervical milieu due to the serpentine nature of the cervix. The only alternatives have been surgical procedures such as laparotomy or laparoscopy. In this paper, we report our experience with a new technique for ultrasound-guided sampling of spermatozoa in the macaque uterus. Twenty adult female cynomolgus macaques were monitored for menses (first day of menses = day l), and one mating per cycle was allowed on day 10, 11, or 12. In one group of ten animals, cervical mucus was sampled at 3 or 18 hr postcoitus (pc) and ultrasound-guided uterine aspiration was performed at 24 hours pc. In a second group of ten monkeys, uterine aspiration was at six hr pc and sperm numbers and motility were counted in the uterine fluid. Uterine fluid was obtained from fourteen of twenty monkeys. Pregnancy occurred in ten of the twenty experimental cycles. Ultrasound-guided uterine aspiration appears to be a reliable method for the evaluation of sperm transport in female macaques. The correlations between uterine sperm recovery and cervical mucus sperm populations arc discussed. The high conception rate in treatment cycles indicates that this procedure can be performed without apparent risk to pregnancy. 相似文献
217.
Food restriction or decreasing the ratio of [Na+, K+] to Ca++, Mg++J in the diet of female rats before conception favoured the production of female offspring. Seven days of food deprivation decreased uterine fluid GPC diesterase activity in female rats, whereas long-term food restriction (21 days), rather than decreasing the enzyme activity, apparently stimulated it. Dietary Ca and Mg supplementation, likewise, produced significant decrease in GPC di esterase activity. A significantly positive correlation was observed between the levels of uterine GPC diesterase and secondary sex ratio change, which indicates that these dietary techniques of sex-ratio manipulation may modulate the uterine fluid GPC diesterase activity and influence sex determination in utero. 相似文献
218.
动情周期、妊娠期与产后大鼠离体子宫的肾上腺素能效应 总被引:1,自引:0,他引:1
本文观察不同机能状态下133个大鼠子宫标本的自发活动,分析了不同机能状态下108个子宫标本的β受体效应与190个子宫标本的α受体效应。 大鼠离体子宫标本的自发收缩频率,在动情间期时明显高于自然动情期,妊娠期与产后的收缩频率介于动情间或与动情期之间。动情期的收缩张力明显高于动情间期,晚孕期的张力则最高。张力或张力频率乘积的数值与妊娠天数呈明显正相关。 整个妊娠期间子宫对异丙基肾上腺素的敏感性明显高于动情期、动情间期或产后,提示妊娠期间子宫中的β受体量可能有所增多。动情期对异丙基肾上腺素的敏感性似比动情间期稍高。 根据子宫对α受体激动剂与阻断剂的反应表明,动情间期的子宫中α受体可能很少,自然与诱发动情期的α受体可能较多,而妊娠期与产后的子宫α受体量可能介乎两者之间。 相似文献
219.
Relationship of uterine infections and folliculogenesis in dairy cows during early puerperium 总被引:1,自引:0,他引:1
Postpartum uterine infections have been associated with reduced fertility in dairy cows; however, the mechanism by which uterine infections limit reproductive function has not been clearly determined. The purpose of this study was to elucidate the relationship between uterine infections in the early puerperium and the onset of folliculogenesis in dairy cows. The pattern and intensity of uterine infections and follicular dynamics were studied in cows that shed fetal membranes (n = 18), and in those that retained fetal membranes after parturition (n = 18). Endometrial swabs collected aseptically from each animal on Days 4, 8 and 12 after parturition were cultured. Ultrasound scanning of the ovaries was carried out on Days 4, B and 12 using a B mode, real-time, linear array ultrasound scanner. The total number of follicles was recorded, and the follicles were classified according to size as small (2 to 4 mm) or medium (5 to 7 mm).
The severity of infection was higher (P<0.05) in retained placenta cows on Days 4, 8 and 12 compared to nonretained placenta cows. The total number of follicles was larger (P<0.05) in nonretained placenta cows on Days 4, 8 and 12 than in retained placenta cows. The distribution of different sizes of follicles on all days of observations was similar in both groups of cows (P>0.05). These data support the hypothesis that uterine infection may delay the initiation of folliculogenesis and suppress the rate of follicular growth in dairy cows in the immediate postpartum period. 相似文献
220.
Yiqi Gao Tao Xue MD Biliang Chen MD Hong Yang MD Li Wei MD 《Developing world bioethics》2023,23(1):34-40
The recent advances in assisted reproductive technology, such as hormonal stimulation, IVF, and intracytoplasmic sperm injection (ICSI), have made it possible to circumvent many causes of male and female factor infertility. However, uterine infertility is still considered an ‘‘unconditionally infertile’’ condition. Owing to the continued advances in organ transplantation, microvascular anastomosis techniques, and immunosuppressive medicine, the transplantation of organs is no longer restricted to the ones necessary for continued life. Quality-of-life enhancing types of transplantation, such as uterine transplantation, in recent years, have also entered the clinical arena. This undoubtedly brings new hope to such women, but also creates ethical challenges. Selection of the donor, the impact on the recipient and offspring, as well as challenges to moral and social norms are issues that cannot be ignored. In the present review, the ethical issues of transplantation of the uterus will be discussed in light of recent progress in the procedure. 相似文献